Every now and then one of these terrible instruments of warfare burst to pieces, killing its crew, as a German shell struck in a vital spot, but, for the most part, they advanced unharmed.
Over the German trenches they plowed their path, as though there was nothing in the way to bar their progress. Walls, earth, and human bodies were crushed beneath them, and they passed on as though nothing had happened. In vain the Germans charged straight up to their sides. There was nothing they could do when they reached the monsters, except to fire ineffectual rifle shots in an effort to penetrate the apertures and reach the gunners, or to hurl hand grenades, which had no effect.
Each time the enemy charged it was never to return. While they wasted their energies attempting to put the tanks out of commission, British infantry mowed them down with, rifle fire. At length these attempts were given up.
The Germans, after an hour's desperate fighting, deserted their first-line trenches, and sought the shelter of the second; from these they were driven to the third.
Hal and Chester found themselves in the midst of the fighting, alongside the heroic Canadians of Vimy Ridge fame. The part of the field in which they found themselves was to the extreme north of the Hindenburg line, almost opposite Douai.
Time after time the Canadians drove the foe back at the point of the bayonet. The Canadians, it appeared soon after noon, had been the most successful of the entire British army. They had pushed their lines almost to Douai. To the south, General Byng's forces had not advanced quite so far.
Suddenly there was an explosion inside a tank scarcely a hundred feet from Hal and Chester. Great clouds of earth ascended into the air. The tank stopped stock still. Apparently it was undamaged, but it proceeded no further. A moment later, the armored door swung open, and the half-dozen men who composed its crew got out.
"Something the matter with the engine," one said in reply to a question by a Canadian officer.
Members of the tank's crew secured rifles and joined the advancing infantry. Hal pressed close to Chester.
"I've a hunch I can fix that thing so it will run," he shouted to make himself heard above the din of battle.